Flos Lonicerae: A Review of Chemical Structures and Biological Activities of Phenolic Derivatives

Flos Lonicerae, a widely used Vietnamese medicinal material, is the dried buds or flowers of Lonicera japonica Thunb., and several other species of genus Lonicera such as Lonicera dasystyla Rehd., Lonicera confusa DC., Lonicera cambodiana Pierre ex Danguy, belonging to the family Caprifoliaceae. This material has been used for a long time in traditional medicine for clearing heat, removing toxins, and dispersing wind heat. According to a variety of recent phytochemistry and biological studies that we systematically summarized, Flos Lonicerae contains 129 phenolic derivatives including 48 flavonoids, 13 lignans and neolignans, 55 phenolic acid derivatives, and 13 other phenolic compounds. These phenolic compounds have remarkable biological effects such as antibacterial, antiviral, antioxidant, anti-inflammatory, anti-cancer, hepatoprotective, anti-endotoxin, anti-allergic, anti-diabetic, cardioprotective, anti-allergic activities, etc. In particular, chlorogenic acid, a prominent component with significant biological activities, is utilized as a marker compound to evaluate the quality of Flos Lonicerae in the Vietnamese and Chinese Pharmacopoeia.